The message "Windows has stopped this device because it has reported problems. (Code 43)" appears in Device Manager on the Bluetooth adapter, with a yellow warning triangle. Code 43 means the device driver told Windows the device failed, so Windows shut it down to prevent further problems, and in most cases it is a driver problem rather than dead hardware.
Fix it, in order
Restart the PC. A full restart clears the driver state and lets Windows re-initialize the adapter from scratch. Use Start, Power, Restart, not Sleep or Hibernate, which preserve the failed state.
Run the Bluetooth troubleshooter. Open Settings, System, Troubleshoot, Other troubleshooters, and select Run next to Bluetooth. It checks the service and driver state and can clear a Code 43 in simple cases.
Disable and re-enable the adapter. In Device Manager, expand Bluetooth, right-click the adapter, and select Disable device. Wait a few seconds, right-click it again, and select Enable device. This forces Windows to reload the driver without removing it.
Restart the Bluetooth Support Service. Press Win + R, type services.msc, and press Enter. Right-click Bluetooth Support Service and select Restart, and make sure its Startup type is not Disabled.
Uninstall the driver completely. In Device Manager, right-click the adapter, select Uninstall device, and check Attempt to remove the driver for this device if the box appears. Then restart the PC so Windows installs a fresh driver.
Remove hidden related devices too. In Device Manager, select View, then Show hidden devices, and uninstall any greyed-out Bluetooth entries as well. A stale hidden entry can keep handing Windows the same broken driver on every reinstall.
Install the driver from the PC maker. Download the Bluetooth or wireless driver package for your exact model from the maker's support site, including the chipset driver if one is listed. A Code 43 that survives a Windows driver reinstall is often a mismatch between the Bluetooth driver and the chipset driver.
Roll back if it started after an update. In Device Manager, open the adapter Properties, open the Driver tab, and select Roll Back Driver. Windows Update sometimes installs a driver that conflicts with the hardware.
Do a cold shutdown. Hold Shift, select Start, then Power, then Shut down, and wait one minute before starting the PC again. This drains the standby power that can keep a Bluetooth chip in a failed state across restarts.
Code 43 is a driver failure report, not a diagnosis of broken hardware. Do not replace the wireless card until a clean manufacturer driver install and a cold shutdown have both failed.
If it still happens
If Code 43 returns on every boot after a clean manufacturer install, test whether the adapter also fails in the BIOS or on a live USB system, which rules out Windows entirely. A Code 43 that follows the hardware across systems, or appears alongside an Unknown USB Device entry, points to the wireless card itself, and on most laptops that card is a replaceable module.
Common questions
What does Code 43 actually mean? It means a driver controlling the device notified Windows that the device failed, so Windows stopped it. The driver is usually the problem, which is why a clean reinstall fixes most Code 43 cases.
Code 43 started right after a Windows update. What do I do? Roll back the Bluetooth driver in Device Manager, or install the wireless driver package from the PC maker's site. The update likely installed a driver that conflicts with your adapter.
What is the difference between Code 43 and Code 45? Code 43 means the device reported a failure and Windows stopped it, while Code 45 means Windows thinks the hardware is not connected at all. Code 43 is a driver problem, Code 45 is a connection or power problem, and the fixes differ.